OFFSET
1,4
EXAMPLE
Some solutions for n=6
..1..1..1..1..1..1....2..2..1..1..0..0....2..2..0..0..1..1....0..0..3..3..1..1
..1..3..3..1..1..1....2..2..1..1..0..0....2..2..0..0..1..1....0..0..3..3..1..1
..1..3..3..1..2..2....1..1..2..2..3..3....0..0..1..1..2..2....3..3..2..2..1..1
..1..1..1..1..2..2....1..1..2..2..3..3....0..0..1..1..2..2....3..3..2..2..1..1
..1..1..2..2..0..0....0..0..3..3..2..2....1..1..2..2..0..0....1..1..1..1..2..2
..1..1..2..2..0..0....0..0..3..3..2..2....1..1..2..2..0..0....1..1..1..1..2..2
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin Mar 31 2012
STATUS
approved